1. Field of the Invention
The present invention relates to a multilayer ceramic capacitor.
2. Description of the Related Art
In recent years, in a multilayer ceramic capacitor, a dielectric layer (interlayer dielectric layer) between facing internal electrode layers has become thinner, and the number of dielectric particles composing the interlayer dielectric layer has become smaller to realize a larger capacity with a compact body, and characteristics of a capacitor have been largely affected: by control of the particle structure.
For example, in the patent article 1, there has been proposed a technique for realizing high dielectric permittivity without deteriorating electric characteristics by controlling the structure of an interlayer dielectric layer in a multilayer ceramic capacitor composed of a dielectric layer and an internal electrode layer. In this technique, the interlayer dielectric layer includes a plurality of dielectric particles, and the plurality of dielectric particles are composed of contact dielectric particles contacting the internal electrode layer and noncontact dielectric particles not contacting the internal electrode layer. An average particle diameter D50e of the contact dielectric particles is larger comparing with an average particle diameter D50d of the noncontact dielectric particles, and the structure to satisfy (D50e/D50d)=1.05 to 1.20 is preferably applied. Note that the patent article 1 describes to use an internal electrode layer paste added with an additive component for accelerating grain growth, but a composition of the additive component is different from that of dielectric particles.
In the technique disclosed in the patent article 1, it is liable that characteristics (a bias characteristic at 85° C.) of an obtained capacitor declines when the interlayer dielectric layer is made thin, for example, to 3.5 μm or less.
Patent Article 1: the Japanese Unexamined Patent Publication No. 2003-124049